Not Applicable
1. Field of the Invention
This invention relates generally to devices and constructs used to effect subterranean drainage from building entrenchments, such as footings, foundations and walls, where seepage and ground water are a problem, and also under garage and basement floors where overburden of concrete exacerbates the drainage problem. More specifically, this invention embodies an improvement to known devices that can be treated as a rigid apparatus, with respect to installation; yet, it can be rolled up in one or two directions, as well as in two alternate directions.
2. Discussion of Relevant Art
A late development in drainage devices is seen in U.S. Pat. No. 5,857,297, issued to Sawyer in 1999, entitled: FOUNDATION WALL CONSTRUCTION (""297). This device is a rigid, plastic xe2x80x9csandwichxe2x80x9d, defined by two parallel plastic sheets (or surfaces) that are integrally formed with and set apart by a multiplicity of parallel partitions, which effect a plurality of channels. Thus, it is a rigid, monolithic structure; and, it bears perforations in the sheet facing the soil. Generally, the ""297 device, like all such apparatus, is installed with a filter fabric adjunct, or large aggregate, interposed the soil and the perforations. Being rigid, it lacks the rollup capability sought by the instant inventor; and thus, it is principally this device that is improved herein. Use of the Sawyer article, as well as the instant invention, with geo-textile filter fabrics is well-known in the field.
As indicative of the art that pre-existed before the above patent, U.S. Pat. No. 3,888,087, for FOUNDATION WALL PROTECTIVE SHEET (""087), offers one of the first devices for providing dimples (posts or detents), as a stand-off mechanism for spacing a filter fabric from the core (base) of the device, and a physical folding crease to accommodate bending about a foundation. This apparatus is quite flexible, but using only a filter fabric as a second ply, it lacks the overburden capability of ""297. The instant inventor incorporates the stand-off concept with his improvements and, while acknowledging the requirement for filter fabric for most installations, avoids the high flexibility character of ""087.
Because they show both the present state of the art in drainage devices having an ostensible sandwich structure, as well as disclosing various standoff mechanisms, U.S. Pat. Nos. 5,857,297 and 3,888,087 are hereby incorporated by reference.
Generally throughout this disclosure, words of description and claim shall have meanings given by standard English usage; however, certain words will be used that may have a more stylistic meaning and are defined as follows:
constructxe2x80x94herein, generally, an article or a building structure;
continualxe2x80x94having intermittent, or periodic, breaks or discontinuities;
continuousxe2x80x94having no breaks or discontinuities;
integralxe2x80x94necessary to complete or in itself complete;
partitionxe2x80x94an projection separating two planar sheets, incipiently continuous but rendered continual by various slices, according to the instant teaching;
off-setxe2x80x94a term describing the state of slices, or slice patterns, that are parallel to others of the genre, but not overlapping nor superposedxe2x80x94as opposed to xe2x80x9calternatingxe2x80x9d, which compels an ordered off-setting of patterns;
postsxe2x80x94as used herein, projected elements, also dimples (in prior art) or detents;
rigidityxe2x80x94a physical property of an object wherein the object substantially resists deflection in a particular dimension (direction) or plane;
slicexe2x80x94a through-cut in the surface(s) of the invention that passes through an intervening partition, but does not penetrate the opposite surface; and
unitaryxe2x80x94having wholeness, as in a single unit or monolith composed of plural members.
The above listing is not exhaustive. Certain other stylized terms, used previously or hereafter, are defined at the time of their first usage or placed in quotation marks and used with conventional wording.
The instant inventor has overcome the deficiencies or limitations of the earlier art by providing an inexpensive, easily applied innovation that provides rollup capability to a hitherto, state-of-the art, rigid drain device.
The preferred embodiment of the invention is worked on a pre-existing drainage device that consists in a generally water-impervious, semi-rigid plastic xe2x80x9csandwichxe2x80x9d, having top and bottom planar members separated by a series of parallel partitions or a post matrix, either forming an integral and monolithic unit with the planar members. Foramens are provided on the surface that is interposed the device and a water source, such as ground or under-the-floor seepage. Whether the partition, or post, interstitial paradigm is employed, remains a manufacturer""s and consumer""s choice. In either structure, channels are formed for the communication of waters through a surface of the sandwich and into a drainage network. The pristine sandwich device is, in itself, capable of withstanding considerable overburden without collapsing; however, it is quite rigid and must be cut several times, on site, to conform to discontinuities in the various constructs employing ground water drainage.
The instant invention modifies the sandwich device by placing in it a series of linear slices (xe2x80x9ccutsxe2x80x9d) that imbue the sandwich with the desired high degree of flexibility, while retaining essentially all of its structural strength. In a first, preferred embodiment, sets of parallel slices (see DEFINITIONS, above) are placed in both top and bottom planes of the sandwich device transverse the parallel partition array or between the row-column elements of the post matrix. It is intuitive that the xe2x80x9cslice setsxe2x80x9d must off-set relative to each other, lest the sandwich be cut through. In an alternate embodiment, the first is further modified by a second pair of slice sets, additional to the first, and again, the top slices off-set in respect of the bottom, but running orthogonal to those slice sets of the first. In the second case, the slices pass between partitions and/or posts.
The desired goal being achieved, there is acquired not only a device that has unlimited in-ground use, with high overburden sustainability, but one having a high degree of flexibility that allows compact rolling, for ease in handling, storage and shipment.